Windshear is a generic term referring to any rapidly changing wind currents. A type of weather phenomenon called “microbursts” can produce extremely strong windshear, posing great danger to aircraft. These are local, short-lived downdrafts that radiate outward as they rush toward the ground. As a downdraft spreads down and outward from a cloud, it creates an increasing headwind over the wings of an oncoming aircraft. This headwind causes a sudden leap in airspeed, and the plane lifts. If the pilots are unaware that this speed increase is caused by windshear, they are likely to react by reducing engine power. However, as the plane passes through the shear, the wind quickly becomes a downdraft and then a tailwind. This reduces the speed of air over the wings, and the extra lift and speed vanish. Because the plane is now flying on reduced power, it is vulnerable to sudden loss of airspeed and altitude. The pilots may be able to escape the microburst by adding power to the engines, but if the shear is strong enough, they may be forced to crash.
Conventionally predictive windshear systems are not available for small antenna weather radar installations used by most business and regional systems (BRS) aircraft. Reactive systems are generally available on BRS aircraft but only warn 5-10 seconds after entering a windshear event. Because every second of warning represents approximately 40 feet of altitude loss prevented, moving the windshear system to be accurate at the advance edge may represent the removal of 200 to 400 feet of altitude loss. Weather radar systems may be used to detect certain windshear signatures, however business and regional systems aircraft may have small antennas with broad beam width, low-power, and with fairly little range.
Accordingly, there is a need for a hybrid windshear system which combines data from conventional predictive and reactive windshear systems or from equipment that may be related to predictive and reactive windshear systems and may be available on a BRS aircraft in order to provide the alerting and warning of windshear events.
It would be desirable to provide a system and/or method that provides one or more of these or other advantageous features. Other features and advantages will be made apparent from the present specification. The teachings disclosed extend to those embodiments which fall within the scope of the appended claims, regardless of whether they accomplish one or more of the aforementioned needs.